The invention relates to valve assemblies for pressurized fluid vessels. More particularly, the invention relates to valve assemblies for controlling the filling of such pressurized fluid vessels.
Various valve assemblies constructed to avoid overfilling of pressurized fluid vessels are known. In U.S. Pat. No. 5,282,496 there is disclosed a two-way valve for filling and draining a gas cylinder. The valve assembly includes a float assembly for control of the opening and closing of the valve as a function of the fluid level in the tank so that the valve can be closed when the fluid level corresponds to the predetermined safe capacity of the vessel. However, this traditional valve design directs the incoming fluid jets in the general direction of the float, causing the float and the associated valve control to be disrupted from its normal movement, giving false signals and possible premature closing of the valve before filling is complete.
U.S. Pat. No. 6,076,546 discloses an overflow protection valve assembly in which the valve plunger is separated from the fluid flow to prevent premature closing due to the pressure on the valve plunger. However, fluctuations in the fluid level during filling are translated to the float assembly. The valve plunger is thereby affected by the control link to this fluctuating float as it moves up and down in the volatile fluid level, and can prematurely close.
The present invention seeks to provide an improved valve assembly which provides positive, reliable closure and yet is of simply overall construction.